tr: Translate, squeeze, and/or delete characters
tr [option]… set1 [set2]
tr copies standard input to standard output, performing
one of the following operations:
The set1 and (if given) set2 arguments define ordered
sets of characters, referred to below as set1 and set2. These
sets are the characters of the input that
tr operates on.
The --complement (-c, -C) option replaces
set1 with its
complement (all of the characters that are not in set1).
tr fully supports only single-byte characters.
Eventually it will support multibyte characters; when it does, the
-C option will cause it to complement the set of characters,
whereas -c will cause it to complement the set of values.
This distinction will matter only when some values are not characters,
and this is possible only in locales using multibyte encodings when
the input contains encoding errors.
The program accepts the --help and --version options. See Common options. Options must precede operands.
An exit status of zero indicates success, and a nonzero value indicates failure.
|• Character sets||Specifying sets of characters.|
|• Translating||Changing one set of characters to another.|
|• Squeezing and deleting||Removing characters.|